how to deactivate a licence?
Contact your VAR.
If you can open SOLIDWORKS go into the program to 'Help', 'Deactivate License'. This command releases the license from the machine. This video shows how this is done to move a license off one machine to another (GoEngineer - SOLIDWORKS: License Activation/Deactivation).
Also, on a related note, if you are on SOLIDWORKS 2018 (or 2019 now) you can switch your license over to Online Licensing so you don't need to manually move the license from one machine to another but instead tie the license to a login that will move the license to whatever machine you choose to log into (like this: GoEngineer - SOLIDWORKS: Online Licensing).
thanks for your reply, I cannot open SOLIDWORKS. My harddisk was damaged and we made a copy in order to save the files and changed by a new one and now he ask the activate the licence before opening SOLIDWORKS.
Contacting SOLIDWORKS they tell me to deactivate it or contact the reseller.
Due to the urgency, I asked the reseller where I bought the licence to resolve the problem.
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